The video, taken by a witness, showed the teenage boy, wearing a school uniform, screaming while he was being held by a police officer on Yu Chau Street, Apple Daily reported.

A 49-year-old woman told the police that the boy had stolen an anti-Falun Gong banner stand she had put on the street.

Police told the boy not to move but he was very emotional and kept yelling “no.” Then he was brought into an alley and subdued by four police officers with shields and batons before being take to a police car.

However, after an initial investigation, police came to believe that the teen did not steal the banner. It was also believed that the boy had an emotional-health problem, and it was understood that he was autistic.

A Hong Kong man of Indian origin, named Jacky, 51, witnessed the whole incident and posted the video on social media. He said that around 5pm, when the teenager passed along Yu Chau Street, he slapped the banner stand. Then the woman chased him and accused him of theft.

The woman later argued with the man and challenged him for not being a “real Chinese”. Jacky replied, “I am a Hongkonger.”

Netizens were outraged at the woman for wrongly accusing the boy, and were also angry that the police used what they considered to be excessive violence in apprehending him.

An online petition organized by social workers, teachers and parents urged the Hong Kong Police Force to strengthen frontline officers’ training on how to communicate with people with special needs.